This is an excellent impromptu trick. It requires a double lift, but they are easy double lifts. I always include this trick in my routine. When you do this trick, make sure you put the cards in the spectator's hand.
A cool presentation for Dr. Daley's Last Trick, and a tutorial for it. A pretty easy effect, only using a couple of double lifts, that gets surprisingly incredible reactions. Enjoy! Please note: MAKE SURE YOU DO THIS EFFECT IN YOUR SPECTATOR'S HAND!!!